nuclear-news

The News That Matters about the Nuclear Industry Fukushima Chernobyl Mayak Three Mile Island Atomic Testing Radiation Isotope

Particles From Cold War Nuclear Bomb Tests Found in Deepest Parts of the Ocean

Particles From Cold War Nuclear Bomb Tests Found in Deepest Parts of the Ocean

Crustaceans in the Mariana Trench and other underwater canyons feed on food from the surface laced with carbon-14 from Cold War bomb tests, By Christopher Crockett, smithsonian.com , May 1, 2019 

Crustaceans in the Mariana Trench and other underwater canyons feed on food from the surface laced with carbon-14 from Cold War bomb tests
The first test of a thermonuclear weapon, or a hydrogen bomb, codenamed Ivy Mike and conducted by the United States in 1952 over the island of Elugelab in Enewetak Atoll in the Pacific Ocean. (Public Domain)……… Crustaceans in the Mariana Trench and other underwater canyons feed on food from the surface laced with carbon-14 from Cold War bomb tests

No place on Earth is free from human influence—not even the bottom of the deepest trenches in the ocean.

Shrimp-like critters from three West Pacific ocean trenches were found to munch on food that sinks down from the surface, leaving a unique chemical signature from decades-old nuclear bomb tests in the bodies of the deep-sea crustaceans. The findings, published recently in Geophysical Research Letters, not only help marine scientists figure out how these bottom dwellers survive, but also underscore the depths to which humanity’s influence can penetrate………

In those dark depths, one of the most common critters is the shrimp-like amphipod, a family of crustaceans that scavenge the ocean floor for food. Where that food comes from is a matter of debate. Potential sources include morsels that percolate up from Earth’s interior, nutrient-rich sediment that slides down steep trench walls, or tasty detritus that wafts down from the surface.

A recent haul of deep-sea amphipods offered Sun and colleagues a chance to solve this marine mystery. Using baited traps, two Chinese research vessels in 2017 harvested amphipods from three trenches in the West Pacific, including the famous Mariana Trench. Sun’s team chemically analyzed the amphipods’ muscle tissue and gut contents and found elevated levels of carbon-14, a heavy variant of carbon. The levels closely matched abundances found near the surface of the ocean, where the amount of carbon-14 is higher than usual thanks to nuclear bomb tests conducted more than half a century ago.

Carbon comes in a few different varieties based on how many neutrons are stuffed into its atomic nucleus. About one out of every trillion carbon atoms on Earth has two extra neutrons. This form, known as carbon-14, occurs naturally thanks to high-speed atomic particles from deep space whacking into nitrogen atoms. But in the middle of the 20th century, humans doubled the amount of carbon-14 in the atmosphere.

According to the International Atomic Energy Agency, from 1945 to 1963 the United States and the Soviet Union (with a little help from the United Kingdom and France) detonated nearly 500 nuclear bombs, 379 of which exploded in the atmosphere. These tests dramatically increased the amount of carbon-14 on our planet. The Test Ban Treaty of 1963 put a stop to most atmospheric and underwater tests, and carbon-14 levels in the atmosphere started a slow return to normal—though they are still higher than pre-nuclear levels—as ocean waters and land-based life absorbed carbon from the air.

………While the nuclear bomb signature has been recorded a couple miles down in the West Atlantic, no one has seen it as these depths before. “This is just interesting as all get out,” says Robert Key, a Princeton oceanographer who was not involved with this study. He points out that starting about a mile below the surface of the North Pacific, carbon-14 levels closely match what the atmosphere looked like before the bomb tests. “The high carbon-14 [in the amphipods] could only come from food that’s come down from the top,” he says.

The abundance of material created in nuclear bomb tests high in the sky found in the bodies of deep-dwelling amphipods underscores a very intimate connection between human activity and the most isolated reaches of the sea…………. https://www.smithsonianmag.com/science-nature/particles-cold-war-nuclear-bomb-testing-found-amphipods-mariana-trench-180972078/

May 2, 2019 - Posted by | oceans, wastes, weapons and war

No comments yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: